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Date: Thu, 18 Oct 2012 22:49:31 +1100
Subject: Re: use of exec()
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:31629

On Thu, Oct 18, 2012 at 10:41 PM, lars van gemerden
<lars@rational-it.com> wrote:
> NameError: name 'function' is not defined
>
> which seems an odd error, but i think some global variable is necessary for this to work (if i put in globals() instead of {}, it works).

The def statement simply adds a name to the current namespace. This
should work (untested):

class _functioncode(code):
    def _creat_func_(self):
        ns={}
        exec("def function(%s):\n\t%s" % (", ".join(type(self).args),
                                          "\n\t".join(self.split('\n'))),ns,ns)
        return ns.function

But it's going to be eternally plagued by security issues. You may
want, instead, to look at literal_eval from the ast module; but that
won't work if you need anything other than, as the name suggests,
literals.

ChrisA